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  • HBaseAPI

    环境准备

    新建项目后在pom.xml中添加依赖:

    <dependency>
        <groupId>org.apache.hbase</groupId>
        <artifactId>hbase-server</artifactId>
        <version>1.3.1</version>
    </dependency>
    
    <dependency>
        <groupId>org.apache.hbase</groupId>
        <artifactId>hbase-client</artifactId>
        <version>1.3.1</version>
    </dependency>
    
    <dependency>
        <groupId>jdk.tools</groupId>
        <artifactId>jdk.tools</artifactId>
        <version>1.8</version>
        <scope>system</scope>
        <systemPath>${JAVA_HOME}/lib/tools.jar</systemPath>
    </dependency>

    HBaseAPI

    获取Configuration对象

    public static Configuration conf;

    static{

        //使用HBaseConfiguration的单例方法实例化

        conf = HBaseConfiguration.create();

    conf.set("hbase.zookeeper.quorum", "192.168.9.102");

    conf.set("hbase.zookeeper.property.clientPort", "2181");

    }

     判断表是否存在

    public static boolean isTableExist(String tableName) throws MasterNotRunningException,

     ZooKeeperConnectionException, IOException{

        //在HBase中管理、访问表需要先创建HBaseAdmin对象

    //Connection connection = ConnectionFactory.createConnection(conf);

    //HBaseAdmin admin = (HBaseAdmin) connection.getAdmin();

        HBaseAdmin admin = new HBaseAdmin(conf);

        return admin.tableExists(tableName);

    }

    创建表

    public static void createTable(String tableName, String... columnFamily) throws

     MasterNotRunningException, ZooKeeperConnectionException, IOException{

        HBaseAdmin admin = new HBaseAdmin(conf);

        //判断表是否存在

        if(isTableExist(tableName)){

           System.out.println("表" + tableName + "已存在");

           //System.exit(0);

        }else{

           //创建表属性对象,表名需要转字节

           HTableDescriptor descriptor = new HTableDescriptor(TableName.valueOf(tableName));

           //创建多个列族

           for(String cf : columnFamily){

               descriptor.addFamily(new HColumnDescriptor(cf));

           }

           //根据对表的配置,创建表

           admin.createTable(descriptor);

           System.out.println("表" + tableName + "创建成功!");

        }

    }

    删除表

    public static void dropTable(String tableName) throws MasterNotRunningException,

     ZooKeeperConnectionException, IOException{

        HBaseAdmin admin = new HBaseAdmin(conf);

        if(isTableExist(tableName)){

           admin.disableTable(tableName);

           admin.deleteTable(tableName);

           System.out.println("表" + tableName + "删除成功!");

        }else{

           System.out.println("表" + tableName + "不存在!");

        }

    }

    向表中插入数据

    public static void addRowData(String tableName, String rowKey, String columnFamily, String

     column, String value) throws IOException{

        //创建HTable对象

        HTable hTable = new HTable(conf, tableName);

        //向表中插入数据

        Put put = new Put(Bytes.toBytes(rowKey));

        //向Put对象中组装数据

        put.add(Bytes.toBytes(columnFamily), Bytes.toBytes(column), Bytes.toBytes(value));

        hTable.put(put);

        hTable.close();

        System.out.println("插入数据成功");

    }

     删除多行数据

    public static void deleteMultiRow(String tableName, String... rows) throws IOException{

        HTable hTable = new HTable(conf, tableName);

        List<Delete> deleteList = new ArrayList<Delete>();

        for(String row : rows){

           Delete delete = new Delete(Bytes.toBytes(row));

           deleteList.add(delete);

        }

        hTable.delete(deleteList);

        hTable.close();

    }

    6.2.7 获取所有数据

    public static void getAllRows(String tableName) throws IOException{

        HTable hTable = new HTable(conf, tableName);

        //得到用于扫描region的对象

        Scan scan = new Scan();

        //使用HTable得到resultcanner实现类的对象

        ResultScanner resultScanner = hTable.getScanner(scan);

        for(Result result : resultScanner){

           Cell[] cells = result.rawCells();

           for(Cell cell : cells){

               //得到rowkey

               System.out.println("行键:" + Bytes.toString(CellUtil.cloneRow(cell)));

               //得到列族

               System.out.println("列族" + Bytes.toString(CellUtil.cloneFamily(cell)));

               System.out.println("列:" + Bytes.toString(CellUtil.cloneQualifier(cell)));

               System.out.println("值:" + Bytes.toString(CellUtil.cloneValue(cell)));

           }

        }

    }

    6.2.8 获取某一行数据

    public static void getRow(String tableName, String rowKey) throws IOException{

        HTable table = new HTable(conf, tableName);

        Get get = new Get(Bytes.toBytes(rowKey));

        //get.setMaxVersions();显示所有版本

        //get.setTimeStamp();显示指定时间戳的版本

        Result result = table.get(get);

        for(Cell cell : result.rawCells()){

           System.out.println("行键:" + Bytes.toString(result.getRow()));

           System.out.println("列族" + Bytes.toString(CellUtil.cloneFamily(cell)));

           System.out.println("列:" + Bytes.toString(CellUtil.cloneQualifier(cell)));

           System.out.println("值:" + Bytes.toString(CellUtil.cloneValue(cell)));

           System.out.println("时间戳:" + cell.getTimestamp());

        }

    }

    6.2.9 获取某一行指定“列族:列”的数据

    public static void getRowQualifier(String tableName, String rowKey, String family, String

     qualifier) throws IOException{

        HTable table = new HTable(conf, tableName);

        Get get = new Get(Bytes.toBytes(rowKey));

        get.addColumn(Bytes.toBytes(family), Bytes.toBytes(qualifier));

        Result result = table.get(get);

        for(Cell cell : result.rawCells()){

           System.out.println("行键:" + Bytes.toString(result.getRow()));

           System.out.println("列族" + Bytes.toString(CellUtil.cloneFamily(cell)));

           System.out.println("列:" + Bytes.toString(CellUtil.cloneQualifier(cell)));

           System.out.println("值:" + Bytes.toString(CellUtil.cloneValue(cell)));

        }

    }

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  • 原文地址:https://www.cnblogs.com/tesla-turing/p/11959945.html
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